Create new PGSQL user

Import SHP files using shp2pgsql-gui

Another handy piece of software shp2pgsql-gui tool. This will allow you to quickly connect to your new PostGIS database and import a Shapefile.
Note this will only work if you have Ubuntu with a desktop (not a headless Ubuntu)

Open terminal, and type:

sudo apt-get install postgis-gui

(Note: this is coming from the main Ubuntu software repository, as it seems the PostgreSQL APT repository doesn't package SHP2PGSQL-GUI anymore...)

Now open the SHP2PGSQL application:

shp2pgsql-gui

Follow the on-screen prompts to load your data.

For more information, visit the ​Boston GIS tutorial in the section "Load Towns Data"

ogr_fdw foreign data wrapper for spatial data

Unfortunately seems PostgreSQL Apt does not include ogr_fdw spatial data wrapper.
The wrapper utilizes GDAL, so much of plumbing needed is already installed for you as part of PostGIS.
Compiling isn't too difficult. On a vanilla Ubuntu, I was able to compile and install with following: